<template>
  <el-breadcrumb class="app-breadcrumb" separator="/">
    <transition-group name="breadcrumb">
      <el-breadcrumb-item :key="item.path" v-for="(item,index) in levelList" v-if="item.meta.title">
        <span class="no-redirect" v-if="item.redirect==='noredirect'||index==levelList.length-1">{{
            item.meta.title
          }}</span>
        <a @click.prevent="handleLink(item)" v-else>{{ item.meta.title }}</a>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script>
  import pathToRegexp from 'path-to-regexp'

  export default {
    data() {
      return {
        levelList: null
      }
    },
    watch: {
      $route() {
        this.getBreadcrumb()
      }
    },
    created() {
      this.getBreadcrumb()
    },
    methods: {
      getBreadcrumb() {
        let matched = this.$route.matched.filter(item => {
          if (item.name) {
            return true
          }
        });
        const first = matched[0];
        if (first && first.name !== 'dashboard') {
          matched = [{path: '/', meta: {title: 'Dashboard'}}].concat(matched)
        }
        this.levelList = matched
      },
      pathCompile(path) {
        // To solve this problem https://github.com/PanJiaChen/vue-element-admin/issues/561
        const {params} = this.$route;
        var toPath = pathToRegexp.compile(path);
        return toPath(params)
      },
      handleLink(item) {
        const {redirect, path} = item;
        if (redirect) {
          this.$router.push(redirect);
          return
        }
        this.$router.push(this.pathCompile(path))
      }
    }
  }
</script>

<style lang="scss" rel="stylesheet/scss" scoped>
  .app-breadcrumb.el-breadcrumb {
    display: inline-block;
    font-size: 14px;
    line-height: 50px;
    margin-left: 10px;

    .no-redirect {
      color: #97a8be;
      cursor: text;
    }
  }
</style>
